This is a summary of SEAN Bulletin, 7(4), April 30, 1982, a publication of the Smithsonian Institution. The complete bulletin is available in the microfiche edition of Eos, as a microfiche supplement, or as a paper reprint. Subscriptions to the SEAN Bulletin are also available. For the microfiche, order document E82-004 at $1.00 from AGU Fulfillment, 2000 Florida Avenue, N.W., Washington, D.C. 20009. For reprints, order SEAN Bulletin (give dates and volume number) through AGU Separates: $3.50 for the first copy for those who do not have a deposit account; $2 for those who do; additional copies are $1.00. For a subscription, order SEAN Bulletin from AGU Fulfillment. The price for 12 monthly issues is $18.00 for a subscription mailed to a United States address, $28.00 (U.S.) if mailed elsewhere. Orders must be prepaid.